United StatesConcerns about the quality of US drinking water have risen sharply following prominent cases of lead pollution and amid growing awareness of emerging pollutants, including ‘forever chemicals’.
It is our conviction that consumers’ thirst for water quality assurance, combined with legal action against polluters, will continue to drive investment opportunities in products and services that enable the removal of these chemicals from drinking water.
Source: Aquasana 2023: 2023 Water Quality Survey
Subhead: Percentage of US households, by year (%)
Overview: This bar chart shows the percentage of US households surveyed that were “familiar with PFAS” and “concerned with unfiltered tap water”, respectively, in 2021, 2022 and 2023.
Overall, this chart illustrates how both public awareness of PFAS and concerns with unfiltered tap water rose sharply between 2021 and 2023.
PFAS have been recognised as harmful
Per- and polyfluoroalkyl substances (PFAS) are a family of thousands of synthetic organic chemicals that have been widely used since the 1940s in a range of applications, from non-stick products to fire-resistant foams. The same qualities that make them so useful – resistance to water and oil – also make them extremely resistant to degradation.
They therefore accumulate in the environment and within living organisms, including humans.1 This matters because research has linked exposure to certain levels of PFAS to the incidence of some cancers, reproductive issues and hormonal disruption, among other health issues.2
The Environmental Protection Agency (EPA), which first regulated PFAS in the early 2000s, introduced enforceable limits on PFAS in US drinking water in 2024. This January, the EPA also announced the addition of nine PFAS to the list of chemicals covered by the Toxics Release Inventory, a public resource to improve transparency about toxic chemicals and pollution prevention activities.3
The Trump administration might raise maximum permissible PFAS levels (from four parts per trillion), delegate environmental regulation to individual states, and reduce funding for enforcement of water quality. Nonetheless, we do not expect PFAS regulation in the US to totally unravel.
Irrespective, government policy is by no means the only catalyst for investment in water treatment solutions.
Litigation and consumer demand drive investment
The health and environmental impacts associated with PFAS are triggering class actions against their manufacturers. Defendants have already agreed to pay more than US$14bn in settlements following claims they had polluted public drinking water in some communities.4
Water utilities are also bringing claims against PFAS makers to compensate them for the costs of water testing and treatment. Under new EPA standards, utilities have three years to conduct testing and a further two to install any necessary water treatment systems.5
This wave of litigation has doubtlessly contributed to rising public awareness: 80% of Americans have reported they are concerned about the presence of PFAS in their homes.6
High-profile local issues have pushed water quality up the agenda more broadly, not least the public health crisis in Flint, Michigan a decade ago. After the city’s drinking water supply was switched and incorrectly treated, residents including around 9,000 children (whose development can be harmed by lead) were exposed to lead-contaminated water for 18 months.7
Opportunities across the water value chain
Investment by utilities to reduce PFAS levels in drinking water, combined with public mistrust of water quality and rising awareness about the health risks associated with PFAS, are driving demand for treatment solutions at both system and household levels. This supports opportunities for innovative businesses in three areas of the water value chain.
First, water filtration equipment. Granular activated carbon and ion exchange are the most commonly used technologies to remove PFAS. The likes of US-listed Pentair manufacture and distribute point-of-use filtration systems that can be installed under kitchen sinks to reduce PFAS concentrations by as much as 98%.8 The market for domestic point-of-use filtration systems is particularly large in the US, where 23mn households (around 15%) rely on private wells.9
Second, environmental consultants that partner with companies to identify and manage PFAS-related risks. Dutch-listed Arcadis has expertise in treating PFAS-contaminated groundwater and drinking water using technologies like foam fractionation, which separates PFAS from water. The company has installed around 30 large-scale water treatment systems worldwide.10
Third, environmental testing solutions. Laboratory service providers like ALS test and analyse water samples for trace levels of compounds and contaminants including PFAS. The Australian-listed company partners with utilities to assure drinking water quality is in accordance with local regulations.
It has been estimated that addressing PFAS pollution in US drinking water will cost US$31bn. Taking wastewater treatment and industrial remediation into account, the addressable market for PFAS treatment solutions could exceed US$200bn in the US alone.11 There are corresponding opportunities across industrialised economies, supporting multi-decade opportunities for investors focused on solutions that can improve the quality of the water we consume.
1 Agency for Toxic Substances and Disease Registry: 2024: Fast Facts: PFAS in the U.S. Population
2 United States Environmental Protection Agency, 2024: Our Current Understanding of the Human Health and Environmental Risks of PFAS
3 United States Environmental Protection Agency, January 2025: EPA Adds Nine Additional PFAS to the Toxics Release Inventory
4 Verisk, 2024: PFAS Litigation Could Generate Billions in Ground-Up Losses. Here’s How
5 United States Environmental Protection Agency, 2024: Biden-Harris Administration Finalizes First-Ever National Drinking Water Standard to Protect 100M People from PFAS Pollution
6 Aquasana, 2024: Aquasana’s 6th Annual Water Quality Survey
7 U.S. Centers for Diseases Control and Prevention, 2024: Story: Flint Water Crisis
8 Pentair, March 2025
9 Pentair, March 2025
10 Arcadis, March 2025
11 Environmental Business Journal / AECOM, 2023
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